In the transporting or shipment of temperature sensitive materials or items such as blood, plasma, vaccines and certain drugs, it is known to use insulated containers which include heating and/or cooling means as disclosed, for example in U.S. Pat. No. 7,913,511, entitled “Cargo Container for Transporting Temperature Sensitive Items”, and issued Mar. 29, 2011; in U.S. Pat. No. 5,950,450, entitled “Containment System for Transporting and Storing Temperature-Sensitive Materials”, and issued Sep. 14, 1999; in U.S. Pat. No. 5,943,876, entitled “Insulating Vacuum Panel, Use of Such Panel as Insulating Media and Insulated Containers Employing Such Panel”, and issued Aug. 31, 1999; in U.S. Pat. No. 5,483,799, entitled “Temperature Regulated Specimen Transporter”, and issued Jan. 16, 1996; and in U.S. Pat. No. 5,603,220, entitled “Electronically Controlled Container for Storing Temperature Sensitive Material”, and issued Feb. 18, 1997; the disclosures of which are incorporated by reference herein. When it is desirable to transport or ship a larger volume of temperature sensitive items, it is desirable to provide a cargo container which is adapted to receive a pallet supporting the temperature sensitive items and which also includes cooling and/or heating means for maintaining the temperature sensitive items within a close predetermined temperature range. Such cargo containers are disclosed, for example, in U.S. Pat. No. 5,187,947, entitled “Wheel Type Freezer and Method for Rapid, Low Temperature Freezing”, and issued Feb. 23, 1993; and U.S. Pat. No. 6,860,115, entitled “Air-Cargo Container, a Refrigerator Unit for an Air-Cargo Container and a Manufacturing Method of an Air-Cargo Container”, and issued Mar. 1, 2005; and in a publication of applicants entitled AcuTemp™ Thermal Pallet Shipper; the disclosures of which are incorporated by reference herein. A Temperature-Controlled, Pallet-Sized Shipping Container is also disclosed in U.S. Pat. Pub. No. 2004/0226309, published Nov. 18, 2004, and the disclosure of which is herein incorporated by reference. This published application claims the benefit of Provisional Pat. Appl'n. No. 60/447,987, filed Feb. 17, 2003, and the disclosure of which is incorporated by reference herein.
In any such cargo container adapted to receive one or more pallets of temperature sensitive items, it may be desirable for the walls and the doors of the cargo container to be insulated with a thermal insulation having a high R-value while minimizing the thickness of the walls and the doors in order to maximize the cargo space and minimize heat transfer to and from the interior of the cargo container. One such type of thermal insulation having a minimal thickness and a high R-value is a vacuum insulated panel (“VIP”). VIPs are known in the art. VIPs may have an R-value between R-30 and R-50. VIPs are generally made by sealing a panel of thermal insulation in a barrier film while subjecting the panel to a vacuum, a process referred to as “evacuating.” The barrier film is formed into a pouch into which the panel of thermal insulation is inserted before the panel is evacuated. Upon being evacuated, the panel is contained within the barrier film in an evacuated state by heat sealing the barrier film.
A cargo container may include a rigid housing. The rigid housing may comprise a rigid outer shell and a rigid inner shell. An interior space, into which flat panel insulation cartridges or cassettes may be inserted, is defined between the inner shell and the outer shell. Each cassette includes one or more layers of VIPs which may be separated by a foam insulation sheet and sandwiched between corrugated protective plastic sheets, all of which are wrapped within a plastic film. The cargo container may further include a refrigeration evaporator, an electrical heating element, circulating fans, a refrigeration compressor, storage batteries, and a control system. It may be desirable to provide through bores, cutouts, and/or reliefs within the VIPs such that refrigeration lines, electrical conduit, etc. may be passed there through or therein or such that the VIPs complement contours of the inner shell and/or outer shell. Other features and advantages of the invention will be apparent from the following description, the accompanying drawings, and the appended claims.
In certain instances, it may be desirable to provide VIPs with through bores having particular geometric shapes. In such instances, a through bore may be formed in the panel of thermal insulation prior to being inserted into the film barrier and subject to evacuation. Once inserted into the film barrier, the panel is evacuated which causes the barrier film to fill the void of the through bore in the panel at which time the barrier film is heat sealed. The barrier film within the through bore may then be cut to the desired geometric shape thus defining a through bore in the VIP. Such a method of forming a through bore may cause the barrier film to gather within the void of the through bore and wrinkle and/or crease which can be detrimental the entire VIP. Thus it may be desirable to develop a method of avoiding wrinkling and creasing of the barrier film when forming through bores in VIPs.
It should be understood that the VIPs, and the methods of making VIPs discussed below, should not be construed as being limited to use with cargo containers, and may be used for any other purpose requiring use of an insulating barrier. For instance, VIPs may be used to insulate hot water heaters, refrigerators, freezers, ranges, and/or any other appliance or device. VIPs may also be used to insulate duct, pipes, and/or tubes including, but not limited to, oil pipelines, hot/cold water piping, and/or HVAC ducts. Additionally, VIPs may be used in vehicles (cars, trucks, planes, boats, etc.) to insulate the passenger compartment, trunk, engine compartment, and/or any other part of the vehicle requiring insulation. Other uses for VIPs are well known in the art, and will be further appreciated from the teachings herein.
The drawings are not intended to be limiting in any way, and it is contemplated that various embodiments of the technology may be carried out in a variety of other ways, including those not necessarily depicted in the drawings. The accompanying drawings incorporated in and forming a part of the specification illustrate several aspects of the present technology, and together with the description serve to explain the principles of the technology; it being understood, however, that this technology is not limited to the precise arrangements shown.